1. Technical Field
The disclosure relates to an ink circulation type inkjet printer.
2. Related Art
There is known an ink circulation type inkjet printer that performs printing by ejecting ink from an inkjet head while circulating the ink.
Japanese Unexamined Patent Application Publication No. 2012-153004 describes an ink circulation type inkjet printer having ink tanks provided upstream and downstream of an inkjet head, and disposed at positions lower than the inkjet head.
When performing printing, such an inkjet printer hermetically seals both the ink tanks by closing air open valves connected to the respective ink tanks. Then, the printer applies a positive pressure to a positive pressure tank that is an ink tank located upstream, and applies a negative pressure to a negative pressure tank that is an ink tank located downstream. Thus, ink flows from the positive pressure tank to the inkjet head. The ink, which is not consumed by the inkjet head, is collected by the negative pressure tank. An air pump delivers the ink from the negative pressure tank to the positive pressure tank. In this manner, the ink is circulated.
When the printing is completed, the air open valves connected to the ink tanks are opened. Thus, the pressures of both the ink tanks change to the atmospheric pressure. Consequently, the circulation of the ink is terminated.